14. Effect of insulin or insulin-like growth factor-I administration at mid-luteal phase of the estrous cycle during superovulation on hormonal profile of Sahiwal cows

S. K. Sheetal, Shiv Prasad and H. P. Gupta

Veterinary World, 11(12): 1736-1741

ABSTRACT

Aim: The present study was designed to study the effect of insulin and insulin-like growth factor-1 (IGF-I) administration during luteal phase of the estrous cycle on the hormonal profile of Sahiwal embryo donor cows during superovulation.

Materials and Methods: Cows (n=18) were selected and divided into three groups; control (n=6, untreated), T-I (n=6, insulin-treated), and T-II (n=6, IGF-I treated). Insulin and IGF-I were given S/C on 5th, 6th, 7th, and 8th days of estrous cycle. Superovulatory treatment was started on day 9th of the estrous cycle. With the sixth dose of follicle-stimulating hormone, prostaglandin was injected to induce superovulatory heat. The superovulated cows were bred, and superovulatory response of each animal was recorded. The embryos were collected non-surgically on the 7th day of superovulatory estrus. About 15 ml blood without anticoagulant was collected on days 5, 7, 9, 11, 13, 15, 17, 19, and 21 or day of embryo recovery where day 0 of estrous cycle was taken as day of estrus. Serum was separated, centrifuged, and transferred into sterilized serum vials. All samples were stored at -20°C till analysis. Progesterone, insulin, and IGF-I were estimated in blood serum by radioimmunoassay using radioimmunoassay kits.

Results and discussion: The mean concentration of progesterone on days 7 and 11, insulin on days 7 and 9, and IGF-I on days 5, 7, 9, 11, and 15 was significantly higher in insulin-treated T-I groups as compared to untreated control.

Conclusions: It may be concluded that exogenous insulin administration during mid-luteal phase may be helpful in follicular and embryonic development through modulation of progesterone, insulin, and IGF-I in indigenous (Bos indicus) Sahiwal embryo donor cows.

Aim: This was a systematic review conducted to evaluate the analgesic drugs and techniques used in the management of pain in dogs undergoing ovariohysterectomy.

Materials and Methods: Systematic searches in PubMed, Google Scholar, and ScienceDirect were conducted for peer-reviewed articles written in English and published from 1995 to 2015. The key search words were dogs, ovariohysterectomy, pain, and analgesics. This was followed by a manual search of the references within the primary data sources. Inclusion and exclusion of studies and data extraction were performed independently by two reviewers. All randomized studies evaluating the effects of analgesics during ovariohysterectomy in dogs were included.

Results: A total of 31 trials met the criteria and were, therefore, included in the study. Data on the type of analgesic drugs used, the technique of administration, and the need for rescue analgesia were extracted from the papers. Individual analgesic protocols were used in 83.9% of the studies compared to multimodal drug therapy, which was used in 16.1% of the studies. Opioids were used in 39.0% of studies, nonsteroidal anti-inflammatory drugs (NSAIDs) in 19.4%, a combination of NSAIDs and opioids in 19.4%, local analgesics in 6.5%, and acupuncture in 3.2% of the studies. Drug administration was done using three approaches that included pre-operative (64.5%), post-operative (22.6%) as well as combined pre- and post-operative approach (12.9%). In 77.4% of the studies, administration of analgesics was done once, while in 12.9%, it was done as a 72-h post-operative course. 24-h and 48-h courses of post-operative pain therapy were done in 6.5% and 3.2% of the studies, respectively. About 57% of the dogs in the control groups required rescue analgesia as compared to 21.6% in the single and 11.3% in multimodal drug therapy groups. The requirement for rescue analgesics was highest in dogs treated using acupuncture (43.8%) and lowest in dogs treated using NSAID-opioid combination (8.6%). Fewer dogs among those that received pain medication preoperatively and postoperatively required rescue analgesia compared to those in groups given drugs before and after surgery only. More dogs (26.4%) among those given analgesics only once postoperatively required rescue analgesia as compared to those that received analgesics daily for 72 h (4.4%).

Conclusions: This study provides evidence that opioids are the mainstream analgesic drugs used in managing acute post-operative pain in dogs' post-ovariohysterectomy. In addition, multimodal drug therapy, particularly, NSAID-opioids combination is more effective for pain management than single drug administration. Administering analgesics both before and after surgery is associated with better outcomes and so is a protracted course of post-operative pain therapy. Although these practices should be encouraged, controlled studies should be conducted to conclusively determine the best practices for pain management in dogs undergoing ovariohysterectomy.

Aim: The present study was carried out to determine the prevalence and molecular detection of fluoroquinolone-resistant Escherichia coli carrying qnrA and qnrS genes in healthy broiler chickens in Mymensingh, Bangladesh, and also to identify the genes responsible for such resistance.

Materials and Methods: A total of 65 cloacal swabs were collected from apparently healthy chickens of 0-14 days (n=23) and 15-35 days (n=42) old. The samples were cultured onto Eosin Methylene Blue Agar, and the isolation and identification of the E. coli were performed based on morphology, cultural, staining, and biochemical properties followed by polymerase chain reaction (PCR) targeting E. coli 16S rRNA genes. The isolates were subjected to antimicrobial susceptibility test against five commonly used antibiotics under fluoroquinolone (quinolone) group, namely gatifloxacin, levofloxacin, moxifloxacin, ofloxacin, and pefloxacin by disk diffusion method. Detection of qnrA and qnrS genes was performed by PCR.

Results: Among the 65 cloacal samples, 54 (83.08%) were found to be positive for E. coli. Antibiotic sensitivity test revealed that, of these 54 isolates, 18 (33.33%) were found to be resistant to at least one fluoroquinolone antibiotic. The highest resistance was observed against pefloxacin (61.11%). By PCR, of 18 E. coli resistant to fluoroquinolone, 13 (72.22%) were found to be positive for the presence of qnrS. None of the isolates were found positive for qnrA.

Aim: An experiment was conducted to evaluate the nutritional, physicochemical, microbiological, and sensory attributes of pork sausages treated with conventional smoking (CS) and liquid smoke (LS).

Materials and Methods: Pork sausages were prepared by employing CS (T1) and by addition of LS at 3% (T2A), 5% (T2B), and 7% (T2C) while smoking was not done in control (C) sausages. The ready-to-eat pork sausages were evaluated in terms of proximate composition, emulsion stability (ES), cooking loss (CL), pH, water activity (aw), texture profile analysis (TPA), and shear force on the day of preparation and the shelf life of the sausages was evaluated on the basis of thiobarbituric acid reactive substance (TBARS) value, organoleptic qualities, total viable plate count, total psychrophilic count, and yeast and mold counts at 5-day interval up to 15 days under refrigerated storage (6±1°C).

Results: The mean percentage moisture and percentage ether extract contents of the conventionally smoked sausages (T1) exhibited significant difference (p≤0.01) with the rest of the formulations. However, in terms of mean percentage crude protein and percentage total solids, no significant difference (p≥0.05) was recorded between the treatment groups. The mean ES (ml of oil/100 g emulsion) of the different sausage emulsions ranged from 1.88 to 3.20, while the mean aw values among the sausage formulations were found to be non-significant. In terms of mean percentage, CL and pH values, significantly lowest (p≤0.01) values were recorded by the T1 sausages. The mean TBARS values recorded at different periods of time in respect of all the treatment groups ranged from 0.10 to 0.33 mg malanoldehyde [MDA]/kg of sausages which are well within the permissible limit. The highest shear force values (KgF) were recorded by the sausages of T1 formulation (p≤0.01), while TPA of the sausages did not record any significant difference (p≥0.05) among the treatments. Organoleptic studies revealed acceptability of the sausages up to 10 days of refrigerated storage irrespective of treatments employed; however, the sausages of T1 formulation scored significantly (p≤0.01) higher panel ratings. Microbiologically, sausages with different formulations were found to be within the acceptable limit up to the 15th day of refrigerated storage.

Conclusion: The study revealed that traditional hot smoking has slightly higher edges over the LS-treated sausages in terms of lipid oxidation, microbiological safety, and sensory panel ratings. However, if not superior, the same was found to be well within the acceptable limit in case of LS-treated sausages proving the potentiality of the use of LS as a suitable replacement for the traditional hazardous hot smoking process.

Aim: Tissue expansion is an applicable technique to reconstruct many surgical defects. The aim of this research was to evaluate the histological changes caused by immediate skin tissue expansion in rats as an animal model.

Materials and Methods: Immediate skin tissue expansion in 18 adult female rats was performed using three different sizes (small, medium, and big) of polymethylmethacrylate tissue expanders at the dorsal surface of the metatarsal area of the right limb. The contralateral limb was served as the control. The tissue expanders were surgically implanted and kept for 15 days.

Results: The immediate skin expansion resulted in histological changes such as the increased thickness of the epidermal layer, the reduction of the dermal layer, an elevated number of fibroblast as well as increased vascularity. Furthermore, skin adnexal structures such as hair follicles and sebaceous glands were farther apart.

Conclusion: The rat skin was able to rapidly adjust and compensate against a specific range of immediate mechanical expansion. The histological changes suggest that the tissues were prepared to withstand the increased external forces, in addition to create possibly additional skin in a relatively short-term period.

Background and Aim: Campylobacteriosis finds its place among the four important global foodborne illnesses. The disease, though self-limiting, needs antibacterial therapy in extraintestinal complications. Therefore, the present study was designed to estimate the prevalence of thermophilic Campylobacters in poultry, animals, and humans of the Kumaon region of Uttarakhand.

Materials and Methods: A total of 609 samples comprising of poultry ceca (n=116), poultry droppings (n=203), and feces of pigs (n=71), cattle (n=61), sheep (n=19), goat (n=17), human beings (n=88), and laboratory animals (n=34) (rats, rabbits, and guinea pigs) were collected. The thermophilic Campylobacters, Campylobacter jejuni and Campylobacter coli were confirmed using multiplex polymerase chain reaction. The isolates were also screened for the presence of virulence genes, and their antibiotic susceptibility testing was done against eight antibiotics.

Results: An overall prevalence of 6.24% was revealed with highest from poultry ceca (15.52%), followed by poultry droppings (5.91%), cattle feces (4.92%), human stools (3.40%), and pig feces (2.82%). The virulence genes, namely cadF, flaA, virB11, and pldA, were present in 38 (100%), 37 (97.37%), 7 (18.42%), and 14 (36.84%) isolates, respectively. All the isolates were resistant to nalidixic acid, while all were sensitive to erythromycin and co-trimoxazole.

Conclusion: It was concluded that the animals and humans in the region harbored the thermophilic Campylobacters which may contribute to the human illness. Resistance shown among the isolates may complicate the antimicrobial therapy.

Aim: The prevalence of cutaneous leishmaniasis (CL) is growing in Iran, and new sources of the disease have been found in the country. The purpose of this study was to describe the epidemiology of CL in Qasr-e Shirin County, Kermanshah Province, West of Iran. Qasr-e Shirin is located near the Iran-Iraq border, and several million pilgrims pass through this area to Iraq every year.

Materials and Methods: A descriptive cross-sectional study was carried out for active case detection from April 1, 2014, to March 31, 2015. All individuals with suspicious lesions were identified through house-to-house visits in the aforementioned area. A questionnaire was filled out for everyone with clinical suspicion of CL. A diagnosis was made based on parasitological examination of the lesion exudate. The annual incidence and prevalence of CL were estimated.

Results: In total, 5277 individuals were randomly screened for the presence of active lesions or scars suspected of CL. The overall prevalence of CL in the County was 4.8% (60 cases had active lesions and 194 cases had scars). All age groups were affected, but the highest incidence of CL was seen in the age group 20-29 years (1.9%). The incidence and prevalence were higher in women than men (5.5% vs. 4%). Most cases (45.6%) had a single lesion or scar and 44 (17.4%) patients had five or more lesions or scars.

Conclusion: The incidence of CL in Qasr-e Shirin County is high. There is a need for further studies on reservoirs and vectors of leishmaniasis in this area. The results of such studies help to perform more efficient and timely spraying against phlebotomine sandfly or detect and decrease the animal reservoir population.

Aim: This study aimed to determine the seroprevalence of peste des petits ruminants (PPR) and bluetongue (BT) in goats' population in the state of Meghalaya of Northeast India.

Materials and Methods: The serosurveillance study was done from the random sampling (n=598) of blood collected from five districts (Ri-Bhoi, East Khasi Hills, West Khasi Hills, Jaintia Hills and West Garo Hills) of Meghalaya. The presence of antibodies against PPR and BT in the samples was detected by indirect enzyme-linked immunosorbent assay (ELISA) method for PPR and competitive ELISA for BT.

Results: The results showed the overall seropositivity of PPR and BT at 7.19% and 60.20%, respectively. West Garo Hills recorded the highest seroprevalence of both PPR (9.81%) and BT (68%) and 3.6% of the samples tested positive for both PPR and BT.

Conclusion: The random survey results indicating the presence of PPR and BT have specific implication in epidemiological perspectives since it highlights the prevalence under natural situations, where the subclinical, inapparent, or non-lethal or recovery of infection was suspected in unvaccinated animals. It also warrants further studies to suggest appropriate control measures to prevent the spread of infection.

Background and Aim: The extensive use of antimicrobials in poultry has led to an increase in bacterial multidrug resistance, and the emergence of multidrug-resistant nontyphoidal Salmonella is a global problem. This study was performed to detect antibiotic-resistant Salmonella serovars in poultry farming and processing environment.

Materials and Methods: A total of 956 various samples, comprising 432 farm origin, 324 poultry processing stage wise and environmental, and 154 product processing stages and environmental samples, were collected from poultry farms and processing units located in and around Mumbai city. Of a total of 71 recovered isolates, 42 randomly selected Salmonella isolates were subjected for antibiotic susceptibility testing by disk diffusion method and serotyping. A total of 31 serotypically confirmed isolates were characterized for the presence of tetA, tetB, blaTEM, and CTX-M gene.

Conclusion: This study revealed that there is a significant rise of Tetracycline resistance with the presence of tetA gene in Salmonella spp. which indicates selective pressure for adopting resistance against tetracycline group of antibiotics.

Aim: This study aimed to investigate the role of ticks in transmission of Enterobacteriaceae bacteria in buffaloes in marshes of the south of Iraq.

Materials and Methods: This survey included 255 healthy and clinically ill buffaloes in marshes of the south of Iraq (Thi- Qar, Basra, and Misan provinces) between the periods from May 2017 to April 2018. Animals were clinically examined. Ticks, isolated from perineum and under tail, sent to the Department of Parasitology, College of Veterinary Medicine, University of Baghdad and University of Thi-Qar for taxonomy. Ticks were dissected, and all internal organs were removed aseptically by forceps to sterile tubes containing brain heart infusion broth and incubated at 37°C for 36 h and subcultured on blood and MacConkey agars at 37°C for 36 h. Biochemical tests including citrate, methyl red, indole, urease, triple sugar iron (H2S), motility tests, and Gram stain were performed.

Results: Two species of ticks were identified. Hyalomma spp. (175; 68.63%) were significantly higher than Rhipicephalus spp. (80; 31.37%). Conversely, pathogenic bacteria in Rhipicephalus spp. (55; 68.75%) was higher than detected from Hyalomma spp. (113; 64.57%), but non-significant. The prevalence of Enterobacteriaceae bacteria in ticks on diseased buffaloes (110; 88.00%) was significantly higher than non-diseased (58; 44.61%). Escherichia coli (123; 73.21%) showed a significantly higher prevalence than Salmonella spp. (25; 14.88%) and Klebsiella spp. (15; 8.92%). There was no significant variation between Salmonella spp. and Klebsiella spp. The latter was significantly higher than Enterobacter spp. (5; 2.97%). The isolation rate of infected tick collected from buffaloes inhabiting marshes was 65 (66.32%), 45 (69.23%), and 58 (63.40%) from Thi-Qar, Basra, and Misan provinces, respectively, with no significant variation. July and August (71.05% and 72.97%) reported the highest among months, while November, December, January, and February recorded nil (0.00%). The summer season was significantly higher (72.72%) followed by autumn (62.06%) and spring (59.77%), while winter reported no any bacterial isolation (0.00%).

Conclusion: The high prevalence of Enterobacteriaceae bacteria isolated from hard ticks supports the probability of transmitting these bacteria to buffaloes in marshes of the south of Iraq.

Materials and Methods: Pigs (n=27) were distributed into three groups (3 replicates of 3 each) and supplemented with basal diet either without probiotics (C) or with a probiotic of dairy-based (Lactobacillus acidophilusNCDC-15; TLact) or swine based (P. acidilactici FT28; TPedic). The probiotics were fed as fermented feed at 200 g/pig/day. At the end of the trial, six pigs from each group were selected for metabolism trial and then sacrificed to determine meat quality and intestinal morphology.

Results: Supplementation of both probiotics improved growth performance, whereas feed intake, digestibility of CP and N retention were better (p<0.05) in P. acidilactici FT28-fed group. However , the digestibility of dry matter (DM), organic matter (OM), ether extracts (EE), crude fibre and nitrogen free extract did not show any significant effect on probiotic supplementation. The serum A: G ratio, triglyceride, and cholesterol level were also improved (p<0.05) in TPedic group compared to other treatment groups. Both probiotic supplementations showed lower (p<0.05) serum glucose level with similar protein and albumin value, which indicated good utilization of feed as well as health status of growing pigs. Dressing percentage, vital organ weight, and EE of loin meat were higher (p<0.05) in probiotic-supplemented groups compared to control. However, P. acidilactici FT28-fed animals showed higher (p<0.05) CP and total ash percentage of meat without affecting pH, water holding capacity, and extract release volume of loin muscle. The villi height and crypt depth were better in both supplemented groups compared to control.

Conclusion: Results of the present study revealed that P. acidilactici FT28 could serve as better probiotic source in swine production for the better utilization of CP and N-retention in meat with improved health status and intestinal morphology.

Aim: Clinical, microbiological, molecular, and pathological assays were undertaken to characterize an outbreak of increasingly reported signs of unresponsive arthritis and pneumonia of Mycoplasma bovis infection in young calves in Jordan.

Materials and Methods: Clinical history of the affected bovine herd was investigated for the presence of respiratory and/ or joint problems. Two calves with such history were clinically examined and necropsied. Representative tissues were sent for microbiological, molecular, and pathological examinations for M. bovis infection.

Results: The outbreak started in a herd of 220 nursing calves, 2 months before the receiving of two calves for postmortem examination. Clinically, respiratory signs and infection of one or more joints dominated in the affected calves. The morbidity and case fatality rates were 27.27% and 61.7%, respectively. The left carpal joint was markedly swollen in both calves and exhibited necrofibrinous to granulomatous arthritis in varying degrees of severity. The anteroventral lung lobes in both calves were consistently affected and revealed multifocal to coalescing severe necrogranulomatous and fibrinopurulent bronchopneumonia. Microbiological and molecular findings confirmed the pathological examination. Furthermore, bovine viral diarrhea (BVD) was diagnosed in one calf by histopathology and polymerase chain reaction.

Conclusion: This investigation reports the first outbreak of M. bovis infection in calves located in Jordan that could occur concurrently with BVD.

Background and Aim: Extending the shelf life of foods is an essential concept in food safety. Most of the time, foods deteriorate through the growth of microorganisms or oxidation process. Essential oils (EOs) derived from plant material have well-documented antioxidant and antibacterial activity. This study aimed to evaluate the effect of Zataria multiflora Boiss EO (ZEO) and Mentha piperita EO (MEO) on the chemical stability of minced meat during storage at 7°C.

Results: pH did not have any significant change during storage. TBA values in the control group were significantly higher than the treatment groups, especially from the 5th day of storage. TVBN in the treatment group was significantly lower than the control group during storage. PV values in the treatment group were significantly lower than the control group during storage.

Conclusion: Results indicate that ZEO and MEO had an excellent antioxidant activity and retarded the spoilage process in minced meat.

Monday, 10 December 2018

1. Epidemiology and economic loss of fasciolosis and dicrocoeliosis in Arak, Iran

Mohsen Arbabi, Elnaz Nezami, Hossein Hooshyar and Mahdi Delavari

Veterinary World, 11(12): 1648-1655

ABSTRACT

Aim: Fasciolosis and dicrocoeliosis are important parasitic diseases worldwide, causing significant financial losses due to decrease in production and viscera condemnation in animals. We performed the current research to assess the epidemiology of these infections and determine their significance from an economic perspective in Arak, Iran.

Materials and Methods: In total, we evaluated 118,463 sheep, 207,652 goats, and 43,675 cattle through necropsic analysis at the slaughterhouses. The average weight of sheep, goat, and cattle liver was 1000, 900, and 5000 g, respectively. The average price of liver in the market was 8 USD/kg. Moreover, the elimination of fundamental nutrients and vitamins was evaluated in infected livers. The prevalence of fasciolosis and dicrocoeliosis was determined. Analysis of variance test was applied for the statistical analysis, and the significance level was <0.05.

Results: In total, Fasciola hepatica and Dicrocoelium dendriticum were detected in 0.56% (confidence interval CI, 0.54-0.59) and 0.77% (CI, 0.75-0.81) of the animals, respectively (p=0.1). The annual economic loss attributed to fasciolosis and dicrocoeliosis was 26698.4 and 30479.2 USD, respectively. The total economic loss was 10,880, 9079.2, and 10,520 dollars in sheep, cattle, and goats, respectively. On the other hand, financial loss resulting from fasciolosis was 7160, 6098.4, and 13,440 dollars in sheep, goats, and cattle, respectively. In addition, economic loss due to dicroceliasis was 10,880, 9079.2, and 10,520 dollars, respectively.

Conclusion: Overall, fasciolosis and dicrocoeliosis in Iran always remain common in sheep, goats, and cattle that afford major economic loss of all the country also exist in Arak province. The present study could provide basic information for further examination of liver fluke infections in Iran.

Background and Aim: Immunoglobulin (Ig) G1 and IgG2a are the surrogate markers respectively for humoral and cellular immune responses of hosts against antigens including cystic fluid proteins of Cysticercus bovis. A study was conducted to investigate the IgG1 and IgG2a responses of Balb/c mice against some individual cystic fluid proteins of C. bovis in an effort to determine the roles of each protein in inducing the humoral and cellular immune responses in host.

Materials and Methods: Individual p71, p31, and p14 proteins of C. bovis were purified by separation of the proteins using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and elution of individual proteins from the gel. Six female Balb/c mice were immunized 4 times at 10-day intervals with the crude cystic fluid proteins, and sera were collected for the measurement of IgG1 and IgG2a levels against the individual proteins. Sera samples collected before the first immunization were used as negative antibody control, sera samples collected after the fourth immunization were used as positive antibody control, and crude cystic fluid protein was used as positive antigen control.

Results: All immunized mice were immune to p71, p31, p14, and crude cystic fluid proteins of C. bovis. The crude cystic fluid proteins of C. bovis induced a higher IgG2a than IgG1 level following the first and the second immunizations but switched into a higher IgG1 than IgG2a level following the fourth immunization. Protein 71 kDa (p71) induced a higher IgG2a than IgG1 level following the fourth immunization. In contrast, p14 induced a higher IgG1 than IgG2a level following the fourth immunization. Low and balance IgG1 and IgG2a levels against p31 were observed following the first to the fourth immunizations.

Conclusion: Using IgG1 and IgG2a levels as the surrogate markers, it appears that cystic fluid antigens of C. bovis induce both humoral and cellular immune responses in Balb/c mice. The p71 appears to be a better inducer of cellular immune response, whereas p14 is a better inducer of humoral immune response of mice.

Aim: The study was aimed to prepare and examine the potential and safety concerns of egg drop syndrome (EDS) vaccine candidate seed. The potential and safety trials of EDS Medan isolate vaccine need to be done before commercial scale of EDS vaccines are made.

Materials and Methods: The safety test of EDS candidate vaccine was tested on 4-week-old specified pathogen-free chickens in an experimentally isolated enclosure.

Results: The result of the safety test obtained 27.3 hemagglutination inhibition (HI) unit of geometric mean titer antibody post-vaccination. However, the potency test of the EDS candidate vaccine was conducted on 17-week-old laying hens. Test results of the EDS potency vaccine in layer obtained antibody titer increased in every week of blood taking with average titer of antibody: Before vaccinated was 22.9 HI unit, 1 week after vaccination was 23.7 HI unit, 2 weeks post-vaccination was 25 HI unit, and 3 weeks after vaccination was 27.3 HI units. In contrast, decreasing trend was observed in control group (unvaccinated chicken).

Conclusion: Serologically, the seed vaccine of EDS virus isolates from Medan was able to produce protective antibody titers starting in the 2nd and 3rd weeks post-vaccination.

17. The first evidence of a new genotype of nephropathogenic infectious bronchitis virus circulating in vaccinated and unvaccinated broiler flocks in Algeria

A. Lounas, K. Oumouna-Benachour, H. Medkour and M. Oumouna

Veterinary World, 11(11): 1630-1636

ABSTRACT

Background and Aim: Avian infectious bronchitis virus (IBV) frequently infects broilers and is responsible for severe economic losses to the poultry industry worldwide. It has also been associated with kidney damage in the broiler flocks. The aim of the present study is to determine the presence of IBV and its possible involvement in kidney damage of broiler chicks.

Materials and Methods: 14 clinically diseased broiler flocks from Western and Central Algeria were sampled and analyzed by hemagglutination inhibition (HI) test and reverse transcriptase-polymerase chain reaction (RT-PCR) followed by phylogenic analysis.

Results: The QX (100%) and 4/91 (60%) IBV serotypes were the most prevalent in the kidney damaged broilers regardless of vaccination status. The molecular detection of avian IBV by RT-PCR identified six samples as positive, of which only two isolates were typable by sequencing. We identified a novel IBDZ13a genotype which showed 93% sequence homology to the partial-S1 gene sequence of the IB 4/91 commercial vaccine strain. Sequencing analysis characterized this virus as a novel and divergent IB 4/91 field virus with eight amino acid substitutions that might have resulted in altered immunogenicity.

Conclusion: The isolation of a new IBV strain (IBDZ13a) from vaccinated broiler flocks may explain the failure of the vaccination programs against IBV field strains. Combination of the HI test and RT-PCR indicated that the nephropathogenic IB outbreaks in broilers are related to this novel strain.

Materials and Methods: The study was conducted from April to May 2017 in Chemini region, Northern Algeria. A total of 60 1-day-old Ross 308 male chicks were divided into three groups consisted of 10 chicks, in each of two replications. The chicks in Group 1 were fed with a standard commercial diet (SCD); Group 2 received the same SCD with 2% supplementation of A. herba-alba powder; and Group 3 received the same SCD with 2% supplementation of O. europaea powder. Growth performance was measured with body weights every 2 weeks, daily feed intake, feed conversion ratio (FCR), and carcass yield at the end of 42 days of rearing. Blood samples were collected to analyze serum glucose, cholesterol, triglycerides, urea, and total protein levels.

Results: Results showed that, at 42 days of rearing, supplementation of O. europaea and A. herba-alba significantly increased (p<0.001) mean body weight (2230.10±26.38 g and 2117.42±26.38 g, respectively, vs. 2336.66±27.88 g in chicks of Group 1), but there was no significant difference (p≥0.05) among the three diets for FCR or percentage carcass yield. Among the serum biochemical parameters, glucose was significantly affected (p<0.01) by supplementation of olive leaf powder (1.90 g/L: Group 3), compared to the SCD (2.24 g/L: Group 1) or Artemisia powder (2.05 g/L: Group 2). Moreover, the supplementation of olive leaf powder in Group 3 broilers significantly affected (p<0.05) the serum cholesterol level (0.95 g/L), compared to the control diet (1.13 g/L). There was no significant difference (p≥0.05) for the other selected serum biochemical concentrations, namely triglycerides, urea, and total protein.

Conclusion: The supplementation of Artemisia or olive leaf powder into the diet for broilers improved body weight by about 5% or 10%, respectively, at slaughter with moderate changes in blood biochemical parameters.